LWTools: lwbasic/parser.c annotate

annotate lwbasic/parser.c @ 34:bfea77812e64

Start of assignment code

author	Lost Wizard (lost@starbug3)
date	Fri, 04 Feb 2011 21:27:03 -0700
parents	890a8f688889
children	cdb0175e1063

rev	line source
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	1 /*
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	2 compiler.c
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	3
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	4 Copyright © 2011 William Astle
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	5
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	6 This file is part of LWTOOLS.
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	7
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	8 LWTOOLS is free software: you can redistribute it and/or modify it under the
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	9 terms of the GNU General Public License as published by the Free Software
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	10 Foundation, either version 3 of the License, or (at your option) any later
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	11 version.
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	12
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	13 This program is distributed in the hope that it will be useful, but WITHOUT
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	16 more details.
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	17
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	18 You should have received a copy of the GNU General Public License along with
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	19 this program. If not, see <http://www.gnu.org/licenses/>.
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	20 */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	21
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	22 /*
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	23 This is the actual compiler bit; it drives the parser and code generation
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	24 */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	25
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	26 #include <stdio.h>
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	27
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	28 #include <lw_alloc.h>
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	29 #include <lw_string.h>
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	30
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	31 #include "lwbasic.h"
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	32 #include "symtab.h"
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	33
34 bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	34 static void expect(cstate *state, int tt)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	35 {
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	36 if (state -> lexer_token != tt)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	37 lwb_error("Expecting %s, got %s\n", lexer_token_name(tt), lexer_return_token(state));
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	38 lexer(state);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	39 }
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	40
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	41
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	42 /* size of a type */
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	43 static int sizeof_type(int type)
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	44 {
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	45 /* everything is an "int" right now; 2 bytes */
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	46 return 2;
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	47 }
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	48
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	49 /* parse a type; the next token will be acquired as a result */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	50 /* the token advancement is to provide consistency */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	51 static int parse_type(cstate *state)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	52 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	53 int pt = -1;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	54
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	55 switch (state -> lexer_token)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	56 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	57 case token_kw_integer:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	58 pt = 1;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	59 break;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	60
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	61 default:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	62 lwb_error("Invalid type specification");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	63 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	64 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	65 /* look for "unsigned" modifier for integer types */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	66 return pt;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	67 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	68
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	69 static void parse_decls(cstate *state)
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	70 {
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	71 /* declarations */
33 890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	72 /* the first thing that doesn't look like a declaration is assumed */
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	73 /* to be a statement and will trigger a bailout */
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	74 int vt;
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	75 char *vn;
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	76 symtab_entry_t *se;
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	77
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	78 for (;;)
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	79 {
33 890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	80 switch (state -> lexer_token)
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	81 {
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	82 /* DIM keyword */
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	83 case token_kw_dim:
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	84 lexer(state);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	85 if (state -> lexer_token != token_identifier)
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	86 {
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	87 lwb_error("Expecting identifier, got %s\n", lexer_return_token(state));
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	88 }
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	89 vn = lw_strdup(state -> lexer_token_string);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	90 lexer(state);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	91 if (state -> lexer_token != token_kw_as)
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	92 {
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	93 lwb_error("Expecting AS, got %s\n", lexer_return_token(state));
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	94 }
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	95 lexer(state);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	96 vt = parse_type(state);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	97
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	98 se = symtab_find(state -> local_syms, vn);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	99 if (se)
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	100 {
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	101 lwb_error("Multiply defined local variable %s", vn);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	102 }
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	103 state -> framesize += sizeof_type(vt);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	104 symtab_register(state -> local_syms, vn, -(state -> framesize), symtype_var, NULL);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	105
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	106 lw_free(vn);
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	107 break;
34 bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	108
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	109 /* blank lines allowed */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	110 case token_eol:
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	111 break;
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	112
33 890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	113 default:
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	114 return;
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	115 }
890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	116 if (state -> lexer_token != token_eol)
34 bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	117 lwb_error("Expecting end of line; got %s\n", lexer_return_token(state));
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	118 lexer(state);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	119 }
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	120 }
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	121
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	122 static void parse_statements(cstate *state)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	123 {
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	124 symtab_entry_t *se;
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	125
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	126 for (;;)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	127 {
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	128 switch (state -> lexer_token)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	129 {
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	130 /* blank lines allowed */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	131 case token_eol:
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	132 break;
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	133
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	134 /* variable assignment */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	135 case token_identifier:
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	136 se = symtab_find(state -> local_syms, state -> lexer_token_string);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	137 if (!se)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	138 {
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	139 se = symtab_find(state -> global_syms, state -> lexer_token_string);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	140 }
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	141 if (!se)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	142 lwb_error("Unknown variable %s\n", state -> lexer_token_string);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	143 lexer(state);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	144 expect(state, token_op_assignment);
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	145
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	146 /* parse the expression */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	147 /* parse_expression(state); */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	148
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	149 /* actually do the assignment */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	150
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	151 break;
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	152
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	153 /* anything we don't recognize as a statement token breaks out */
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	154 default:
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	155 return;
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	156 }
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	157 if (state -> lexer_token != token_eol)
bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	158 lwb_error("Expecting end of line; got %s\n", lexer_return_token(state));
33 890a8f688889 Basic parsing of local variable decls lost@l-w.ca parents: 32 diff changeset	159 lexer(state);
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	160 }
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	161 }
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	162
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	163
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	164 /* issub means RETURNS is not allowed; !issub means RETURNS is required */
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	165
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	166 static void parse_subfunc(cstate *state, int issub)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	167 {
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	168 int pt, rt;
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	169 char subname, pn;
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	170 int vis = 0;
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	171 symtab_entry_t *se;
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	172 int paramsize = 0;
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	173
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	174 state -> local_syms = symtab_init();
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	175 state -> framesize = 0;
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	176
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	177 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	178 if (state -> lexer_token != token_identifier)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	179 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	180 lwb_error("Invalid sub name '%s'", state -> lexer_token_string);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	181 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	182
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	183 subname = lw_strdup(state -> lexer_token_string);
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	184
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	185 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	186 if (state -> lexer_token == token_kw_public \|\| state -> lexer_token == token_kw_private)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	187 {
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	188 if (state -> lexer_token == token_kw_public)
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	189 vis = 1;
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	190 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	191 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	192
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	193 /* ignore the "PARAMS" keyword if present */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	194 if (state -> lexer_token == token_kw_params)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	195 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	196
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	197 if (state -> lexer_token == token_eol \|\| state -> lexer_token == token_kw_returns)
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	198 goto noparms;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	199
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	200 paramagain:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	201 if (state -> lexer_token != token_identifier)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	202 {
31 574931d87abd Created a function to prettyprint the current lexer token lost@l-w.ca parents: 30 diff changeset	203 lwb_error("Parameter name expected, got %s\n", lexer_return_token(state));
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	204 }
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	205 pn = lw_strdup(state -> lexer_token_string);
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	206 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	207
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	208 if (state -> lexer_token != token_kw_as)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	209 lwb_error("Expecting AS\n");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	210 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	211
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	212 pt = parse_type(state);
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	213
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	214 se = symtab_find(state -> local_syms, pn);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	215 if (se)
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	216 {
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	217 lwb_error("Duplicate parameter name %s\n", pn);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	218 }
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	219 symtab_register(state -> local_syms, pn, paramsize, symtype_param, NULL);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	220 paramsize += sizeof_type(pt);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	221 lw_free(pn);
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	222
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	223 if (state -> lexer_token == token_char && state -> lexer_token_string[0] == ',')
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	224 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	225 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	226 goto paramagain;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	227 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	228
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	229 noparms:
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	230 rt = -1;
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	231 if (!issub)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	232 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	233 if (state -> lexer_token != token_kw_returns)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	234 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	235 lwb_error("FUNCTION must have RETURNS\n");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	236 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	237 lexer(state);
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	238 /* if (state -> lexer_token == token_identifier)
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	239 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	240 printf("Return value named: %s\n", state -> lexer_token_string);
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	241
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	242 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	243 if (state -> lexer_token != token_kw_as)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	244 lwb_error("Execting AS after RETURNS");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	245 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	246 }
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	247 */
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	248 rt = parse_type(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	249 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	250 else
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	251 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	252 if (state -> lexer_token == token_kw_returns)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	253 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	254 lwb_error("SUB cannot specify RETURNS\n");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	255 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	256 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	257
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	258
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	259 if (state -> lexer_token != token_eol)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	260 {
31 574931d87abd Created a function to prettyprint the current lexer token lost@l-w.ca parents: 30 diff changeset	261 lwb_error("EOL expected; found %s\n", lexer_return_token(state));
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	262 }
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	263
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	264
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	265 se = symtab_find(state -> global_syms, subname);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	266 if (se)
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	267 {
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	268 lwb_error("Multiply defined symbol %s\n", subname);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	269 }
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	270
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	271 symtab_register(state -> global_syms, subname, -1, issub ? symtype_sub : symtype_func, NULL);
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	272
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	273 state -> currentsub = subname;
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	274 state -> returntype = rt;
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	275 /* consume EOL */
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	276 lexer(state);
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	277
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	278 /* variable declarations */
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	279 parse_decls(state);
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	280
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	281 /* output function/sub prolog */
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	282 emit_prolog(state, vis);
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	283
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	284 /* parse statement block */
34 bfea77812e64 Start of assignment code Lost Wizard (lost@starbug3) parents: 33 diff changeset	285 parse_statements(state);
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	286
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	287 if (issub)
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	288 {
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	289 if (state -> lexer_token != token_kw_endsub)
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	290 {
31 574931d87abd Created a function to prettyprint the current lexer token lost@l-w.ca parents: 30 diff changeset	291 lwb_error("Expecting ENDSUB, got %s\n", lexer_return_token(state));
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	292 }
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	293 }
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	294 else
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	295 {
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	296 if (state -> lexer_token != token_kw_endfunction)
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	297 {
31 574931d87abd Created a function to prettyprint the current lexer token lost@l-w.ca parents: 30 diff changeset	298 lwb_error("Expecting ENDFUNCTION, got %s\n", lexer_return_token(state));
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	299 }
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	300 }
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	301 /* output function/sub epilog */
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	302 emit_epilog(state);
26 26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	303
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	304 lw_free(state -> currentsub);
26aa76da75ad Additional parsing in function/sub; emission of prolog/epilog code lost@l-w.ca parents: 25 diff changeset	305 state -> currentsub = NULL;
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	306 symtab_destroy(state -> local_syms);
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	307 state -> local_syms = NULL;
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	308 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	309
30 bcd532a90e53 Renamed "compiler" to "parser" for more consistent terminology lost@l-w.ca parents: 27 diff changeset	310 void parser(cstate *state)
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	311 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	312 state -> lexer_curchar = -1;
32 49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	313 state -> global_syms = symtab_init();
49d608aecc4d Framework for handling local stack frame and/or variables lost@l-w.ca parents: 31 diff changeset	314
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	315 /* now look for a global declaration */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	316 for (;;)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	317 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	318 state -> parser_state = parser_state_global;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	319 lexer(state);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	320 switch (state -> lexer_token)
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	321 {
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	322 case token_kw_function:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	323 printf("Function\n");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	324 parse_subfunc(state, 0);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	325 break;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	326
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	327 case token_kw_sub:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	328 printf("Sub\n");
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	329 parse_subfunc(state, 1);
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	330 break;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	331
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	332 /* blank lines are allowed */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	333 case token_eol:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	334 continue;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	335
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	336 /* EOF is allowed - end of parsing */
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	337 case token_eof:
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	338 return;
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	339
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	340 default:
31 574931d87abd Created a function to prettyprint the current lexer token lost@l-w.ca parents: 30 diff changeset	341 lwb_error("Invalid token '%s' in global state\n", lexer_return_token(state));
25 87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	342 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	343 }
87590f43e76d Started lwbasic parser; checkpoint lost@l-w.ca parents: diff changeset	344 }

Mercurial > hg > index.cgi

annotate lwbasic/parser.c @ 34:bfea77812e64